A man can row 6 km/h in still water. It takes him twice as long to row upstream as to row downstream. What is the speed of the current?
Q1. A man can row 6 km/h in still water. It takes him twice as long to row upstream as to row downstream. What is the speed of the current?
Answer: 2 km/h
Explanation: Let the speed of the current be x. Then, 6 + x = 2(6 - x). Solving gives 6 + x = 12 - 2x, so 3x = 6, x = 2.